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request vmhost software in-service-upgrade



Perform a unified in-service software upgrade (ISSU). A unified ISSU enables you to upgrade from one Junos OS release and host OS release to another with no disruption on the control plane and with minimal disruption of traffic. For an unified ISSU, graceful Routing Engine switchover (GRES) and nonstop active routing (NSR) must be enabled.

Starting inJunos OS Release 18.2R1, MX10003 routers support unified in-service software upgrade (ISSU) using request vmhost software in-service-upgrade command. MX10003 does not support upgrading Junos OS only image using request system software in-service-upgrade command.


On MX10003 routers:

  • ISSU is not supported on MACsec MIC (JNP-MIC1-MACSEC).

  • ISSU is not supported for the interfaces that are configured with 1-Gigabit Ethernet mode. If ISSU upgrade is carried out in 1-Gigabit Ethernet mode, then the behavior is unexpected and traffic loss can be expected.

  • ISSU is not supported on timing protocols (like, Precision Time Protocol and Synchronous Ethernet), MACsec protocols, and BBE protocols. If these protocols are already enabled, then it will not work after ISSU is enabled.

  • The MAC statistics (retrieved using show interfaces extensive command) are reset during ISSU which means that the MAC statistics does not provide the correct statistics after ISSU.



Location from which the software package or bundle is to be installed. For example:

  • /var/tmp/package-name— For a software package or bundle that is being installed from a local directory on the router.

  • protocol://hostname/pathname/package-name—For a software package or bundle that is to be downloaded and installed from a remote location. Replace protocol with one of the following:

    • ftp—File Transfer Protocol (FTP).

    • http—Hypertext Transfer Protocol (HTTP).

    • scp—Secure Copy Protocol (SCP) (not available for limited editions).


(Optional) When the no-old-master-upgrade option is included, after the backup Routing Engine is rebooted with the new software package and a switchover occurs to make it the new primary Routing Engine, the former primary (new backup) Routing Engine is not upgraded to the new software. In this case, you must manually upgrade the former primary (new backup) Routing Engine. If you do not include the no-old-master-upgrade option, the system automatically upgrades the former primary Routing Engine.


(Optional) Automatically reboot the former primary (new backup) Routing Engine after the ISSU. If you don not include the reboot option in the command, you must manually reboot the former primary (new backup) Routing Engine by using the request vmhost reboot command.


(Optional) (MX Series) Use this option to display the daemon related information during the upgrade.

Additional Information

The following conditions apply to unified ISSU:

  • Unified ISSU is not supported on every platform. For a list of supported platforms, see Unified ISSU System Requirements.

  • Unsupported PICs are restarted during a unified ISSU on certain routing devices.

  • During a unified ISSU, any unsupported protocols running on the device causes packet loss.

  • During a unified ISSU, you cannot bring any PICs online or take them offline on certain routing devices.

Required Privilege Level


Sample Output

request vmhost software in-service-upgrade

Sample Output

request vmhost software in-service-upgrade verbose

Release Information

Command introduced in Junos OS Release 15.1F3.

Option introduced in Junos OS Release 18.2R1 for the MX Series routers.


PTX3000 router supports the Routing and Control Board, RCBPTX.